Plate tectonics is the theory that Earth’s outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. The plates act like a hard and rigid shell compared to Earth’s mantle. This strong outer layer is called the lithosphere. The driving force behind plate tectonics is convection in the mantle. Hot material near the Earth’s core rises, and colder mantle rock sinks.
- Plate tectonic theory
Types of Plate Boundaries
|Name of station||Pinon Flat, California, USA|
|Latitude and longitude||33.611,-116.456|
|Distance from you (in miles)||63.8|
|Date station commenced operation (year, day of year)||1986,297|
|Name of the fault||Dog Valley fault|
|Age of the fault||1,600,000 years|
|Slip rate (this is how fast one side of the fault moves past the other)||0.2mm/yr|
There are two basic approaches: relative age dating, and absolute age dating. Relative age dating uses comparison while absolute age dating requires one to specifically state the age in figures.
- Convergent Plate Boundaries: This plate boundary occurs between two plates that are pushing towards each other. An example is the boundary between the Eurasian Plate and the Indian Plate at the Himalayas.
- Divergent Plate Boundary: This plate boundary exists between two plates that are moving away from each other. An example is the boundary between the Pacific Plate and the Antarctic Plate.
- Transform Plate Boundary: Occurs between two plates that are sliding past each other. An example is the Pacific Plate and the Australian Plate crossing New Zealand.
- USGS Advanced National Seismic Station (ANSS) list of ANSS stations closest to California.
- The USGA Earthquake Fault Map and approximate location of the ANSS station
- How Geologists determine the age of a fault line and types of evidence specifically used
Relative age approach assumes that unless something has happened, newer fault lines will always be on top of the older ones while also paying attention to crosscutting relationships such as a volcanic dike or a fault that cuts across several sedimentary layers.
Absolute approach requires you to get the actual age of the fault line. It’s based either on fossils which are recognized to represent a particular interval of time, or on radioactive decay of specific isotopes.
|Name of the plate on which you live||North American Plate|
|Closest neighboring plate(s) to you||Pacific PlateJuan de Fuca PlateCarribean Plate|